392) Which of the following act disturbs the ecological balance?
A) Social Forestry
B) Afforestation
C) Vanamahotsav
D) Lumbering

393) Which of the following alloys is used for making magnets ?
A) Duralumin
B) Stainless Steel
C) Alnico
D) Magnelium

394) Which of the following can be used to absorb neutrons to control the chain reaction during nuclear fission?
A) Boron
B) Heavy water
C) Plutonium
D) Uranium

395) Which of the following cell organelles function as the power house of a living cell?
A) Ribosome
B) Chloroplast
C) Mitochondria
D) Golgi apparatus

396) Which of the following characters is not shown by hydrogen:
A) It burns in air to form water
B) It supports combustion
C) It combines with almost all metals forming hydrides
D) It readily combines with fluorine and chlorine

397) Which of the following Chemicals is used for fruit ripening?
A) Calcium carbide
B) Potassium chloride
C) Sodium chloride
D) Sodium carbonate